"An easy way to understand it is, you're baking the material so it forms to the strength and characteristics that you want," Lefeber says.

After the wings are baked, they'll be moved to Boeing's nearby plant for final assembly.

So, if the wings are made from carbon-fiber reinforced plastic, why not make the 777X fuselage out of the stuff, too?

Short answer: A carbon-fiber composite fuselage would have added much more time to the development process, Boeing says.

With the 777X, Boeing says it wants to maintain the reliability of today's 777 while improvingits economic profile and delivering it at a time when airlines "need it most."

Production is expected to begin in 2017.

The first 777X could enter service as soon as 2020.

Six airlines have placed orders for 320 777Xs, Boeing says, including Emirates, All Nippon Airways and Lufthansa. No U.S.-based carriers are among the six.

Boeing's new X family is part of an engineering revolution that's allowing jetliners with only two engines to fly many of the same global routes as bigger, fuel-guzzling four-engine airliners such as the 747 and the Airbus A380 Super Jumbo.

The range of the 777-9X is expected to reach beyond 14,000 kilometers (8,699 miles).

That's roughly the distance between Dubai, United Arab Emirates, and Panama.

These projects, along with the 777X family, demonstrate that fast-developing technology is pushing the capabilities of the aviation industry forward and changing the way humans travel across the planet.